Breast-feeding still best for babies

Breast milk was long considered the most pure and perfect food we can feed our newborns. And then its reputation was marred in recent years when headlines reported on studies indicating that a mother’s milk contains toxins. For example, two studies, published in August and September 2003, found that American women’s breast milk contained polybrominated diphenyl ethers (PBDEs), commonly used as flame retardants in consumer products such as pajamas and mattresses, at levels 10 to 100 times higher than those previously detected in European women. The news left mothers alarmed and perplexed.

A recent review of data from several studies brings some good news: the benefits of breast-feeding far outweigh the potential risks of toxins. A recent New York Times article reported on the study, which appeared in the current issue Breastfeeding Medicine:

Researchers reviewed data from three studies, among them a Dutch study of 418 infants and mothers, half of whom breast-fed and half of whom used formula; a smaller Dutch study of 38 mothers that assessed the impact of different levels of dioxin exposure; and a German study of 232 mothers and babies who had been exposed to dioxin before birth.

The studies noted minor differences among the exposed babies, such as higher levels of thyroid hormones and lower blood platelet counts, compared to infants who were not exposed to dioxins. But the researchers said these differences did not appear to have any impact on the children’s health and development, and they emphasized that the measures were not abnormal.

At the same time, breast-fed babies scored significantly higher than formula-fed babies on tests of mental development when they were seven months old and again at 18 months, according to the Dutch study.

The journal’s editor, Dr. Ruth Lawrence, said the review was important because many women may have been taken aback by news reports saying that breast milk can be contaminated with chemical pollutants.

“When agencies like the E.P.A. decided to monitor the presence of toxins in the environment through breast milk, people like me said, ‘Please don’t do that–it will be misinterpreted’,” Dr. Lawrence said. She noted that there is also a risk of contamination when using baby formula mixed with tap water.